Antimony-free glass, antimony-free frit and a glass package that is hermetically sealed with the frit

ABSTRACT

An antimony-free glass suitable for use in a frit for producing a hermetically sealed glass package is described. The hermetically sealed glass package, such as an OLED display device, is manufactured by providing a first glass substrate plate and a second glass substrate plate and depositing the antimony-free frit onto the first substrate plate. OLEDs may be deposited on the second glass substrate plate. An irradiation source (e.g., laser, infrared light) is then used to heat the frit which melts and forms a hermetic seal that connects the first glass substrate plate to the second glass substrate plate and also protects the OLEDs. The antimony-free glass has excellent aqueous durability, good flow, low glass transition temperature and low coefficient of thermal expansion.

PRIORITY

This application claims the benefit of priority under 35 U.S.C. §119 ofU.S. Provisional Application Ser. No. 61/870,419 filed on Aug. 27, 2013,the content of which is relied upon and incorporated herein by referencein its entirety.

TECHNICAL FIELD

The present disclosure relates to an antimony-free glass containingboron in an amount to effectively lower the glass transition temperatureof the glass, a frit made therefrom, and a hermetically sealed glasspackages sealed with the frit that is suitable to protect electronicdevices that are sensitive to the ambient environment. Some examples ofsuch devices are organic emitting light diode (OLED) displays, sensors,photovoltaic and other optical devices. Embodiments disclosed herein aredemonstrated using OLED displays as an example.

BACKGROUND

OLEDs have been the subject of a considerable amount of research inrecent years because of their use and potential use in a wide variety ofelectroluminescent devices, and are now reaching commercialization. Forinstance, a single OLED can be used in a discrete light emitting deviceor an array of OLEDs can be used in lighting applications or flat-paneldisplay applications (e.g., OLED displays). OLED displays are known asbeing very bright and having a good color contrast and wide viewingangle. However, OLED displays, and in particular the electrodes andorganic layers located therein, are susceptible to degradation resultingfrom interaction with oxygen and moisture leaking into the OLED displayfrom the ambient environment. It is well known that the life of the OLEDdisplay can be significantly increased if the electrodes and organiclayers within the OLED display are hermetically sealed from the ambientenvironment. Unfortunately, in the past it was very difficult to developa sealing process to hermetically seal the OLED display. Some of thefactors that made it difficult to properly seal the OLED display arebriefly mentioned below:

The hermetic seal should provide a barrier for oxygen (10⁻³ cc/m²/day)and water (10⁻⁶ g/m²/day).

The size of the hermetic seal should be minimal (e.g., <2 mm) so it doesnot have an adverse effect on size of the OLED display.

The temperature generated during the sealing process should not damagethe materials (e.g., electrodes and organic layers) within the OLEDdisplay. For instance, the first pixels of OLEDs which are located about1-2 mm from the seal in the OLED display should not be heated to morethan 100° C. during the sealing process.

The gases released during the sealing process should not contaminate thematerials within the OLED display.

The hermetic seal should enable electrical connections (e.g., thin-filmchromium) to enter the OLED display.

One method for sealing the OLED display is to use different types ofepoxies, inorganic materials and/or organic materials that form the sealafter they are cured, such as by irradiation. For example, some sealsuse a composite-based approach where alternate layers of inorganicmaterials and organic materials can be used to seal the OLED display.Although these types of seals usually provide good mechanical strength,they can be very expensive and there are many instances in which theyhave failed to prevent the diffusion of oxygen and moisture into theOLED display. Another common way for sealing the OLED display is toutilize metal welding or soldering. However, the resulting seal is notdurable in a wide range of temperatures because of the substantialdifferences between the coefficients of thermal expansions (CTEs) of theglass plates and metal in the OLED display.

More recently, glass-based frits have been used to seal glass substrateplates in a glass package that provides excellent hermeticity to theenclosed device. But many of these frits contain toxic elements, such asantimony, which pose environmental hazards. Accordingly, there is a needfor a glass-based frit suitable for hermetically sealing glass packages,such as electronic devices (e.g. for display-type applications), havinga low coefficient of thermal expansion (CTE) that does not containantimony.

SUMMARY

The present disclosure describes an antimony-free glass, a fritcomprising the antimony-free glass and an hermetically sealed OLEDdisplay and method for manufacturing the hermetically sealed OLEDdisplay. Basically, an hermetically sealed OLED display is manufacturedby providing a first glass substrate plate and a second glass substrateplate and depositing the frit onto the second glass substrate plate. Anorganic material, such as those used in the manufacture of an OLED maybe deposited on the first substrate plate. An irradiation source (e.g.,laser, infrared light) is then used to heat the frit which melts andforms a hermetic seal that connects the first glass substrate plate tothe second glass substrate plate and also protects the OLEDs. The fritis an antimony-free glass that includes vanadium, and possibly a CTElowering filler, such that when the irradiation source irradiates thefrit, the frit is heated, softens and forms a bond between the substrateplates while avoiding thermal damage to the OLEDs. Vanadium phosphatefrits, for example, have proven especially suitable for sealing glasspackages of the type just described, and in particularantimony-containing vanadium phosphate frits. Such frits are stable,exhibit high optical absorbance and have excellent mechanical andaqueous durability. Unfortunately, antimony is a toxic element, andefforts have been directed toward finding a replacement for antimonythat does not detrimentally affect the other beneficial attributes ofthe frit.

To that end, the excellent aqueous durability performance of Sb-vanadiumphosphate frits was maintained without Sb₂O₃ by replacement of theantimony oxide by a combination of Fe₂O₃+TiO₂, along with a smalladdition of ZnO to maintain flow performance and B₂O₃ to reduce theglass transition temperature of the glass. The presence of Fe₂O₃ wasfound to have the greatest effect in improving durability. However, itraised T_(g), thus degrading frit flow during sealing. In addition,frits with high Fe₂O₃ levels (equal to or greater than about 25 mole %)tended to be oxidatively unstable, with repeat samples fired to the sameschedule (425° in N₂) exhibiting different colors (brown or black), withmarked differences in the degree of flow. Although TiO₂ alone actuallydegraded aqueous durability to some extent, the combination ofFe₂O₃+TiO₂+B₂O₃ proved to be an ideal combination from the standpoint ofobtaining laser-sealable frits with both high aqueous durability and lowT_(g) (≦365° C.).

Both lab bench tests exposing the glass to 90° C. deionized water aswell as 85° C./85% relative humidity (RH) environmental chamber testingof laser-sealed samples indicate that frits based on theV₂O₅—P₂O₅—Fe₂O₃—TiO₂—ZnO—B₂O₃ system are capable of forming a low Tgfrit that provides excellent sealing properties.

The antimony-free glass may contain V₂O₅ in any amount in the range from≧40 mole % to ≦52.5 mole % where the upper and lower limits of suitableranges fall therein, for example from ≧40 mole % to ≦50 mole %, from ≧40mole % to ≦48 mole %, from ≧42 mole % to ≦50 mole %, from ≧42 mole % to≦52.5 mole %, or from ≧42 mole % to ≦48 mole %.

The antimony-free glass may contain P₂O₅ in an amount from ≧20 mole % to<25 mole %, from ≧20 mole % to <24 mole %, from ≧20 mole % to <23 mole%, or from ≧20 mole % to <22.5 mole %.

The antimony-free glass may contain Fe₂O₃ in an amount from >0 mole % to<25 mole %, from ≧10 mole % to ≦20 mole %, from ≧10 mole % to ≦18 mole%, from ≧10 mole % to ≦16 mole %, from ≧10 mole % to ≦15 mole %, or from≧10 mole % to ≦14 mole %.

The antimony-free glass may contain TiO₂ in an amount from >0 mole % to<25 mole %, from ≧5 mole % to ≦20 mole %, from ≧5 mole % to ≦18 mole %,from ≧5 mole % to ≦15 mole %, or from ≧10 mole % to ≦18 mole %.

The antimony-free glass may contain ZnO in an amount from ≧0 mole % to≦10 mole %, from ≧2 mole % to ≦5 mole %, from ≧0 mole % to ≦4 mole %, orfrom ≧2.5 mole % to ≦5 mole %.

The antimony-free glass may contain B₂O₃ in an amount from >0 mole % to≦20 mole %, from >0 mole % to ≦15 mole %, from >0 mole % to ≦10 mole %,from >0 mole % to ≦7.5 mole %, from ≧1 mole % to ≦20 mole %, from ≧3mole % to ≦20 mole %, or from ≧5 mole % to ≦15 mole %.

TiO₂+Fe₂O₃ may be in a range from 15 mole % to 30 mole %, whileTiO₂+Fe₂O₃+B₂O₃ may be in a range from 25 mole % to 35 mole %, and insome embodiments TiO₂+Fe₂O₃+B₂O₃ may be in a range from 27.5 mole % to35 mole %.

Accordingly, as disclosed herein, an antimony-free glass is describedcomprising:

-   -   V₂O₅≧40 mole % and ≦52.5 mole %;    -   P₂O₅≧20 mole % and <25 mole %;    -   ZnO≧0 mole % and ≦10 mole %;    -   Fe₂O₃>0 mole % and <25 mole %;    -   TiO₂>0 mole % and <25 mole %;    -   B₂O₃>0 mole % and ≦20 mole %; and        wherein TiO₂+Fe₂O₃ is in a range from 15 mole % to 30 mole %.

The antimony-free glass may, for example, comprise:

-   -   V₂O₅≧40 mole % and ≦52.5 mole %;    -   P₂O₅≧20 mole % and <25 mole %;    -   ZnO≧0 mole % and ≦5 mole %;    -   Fe₂O₃≧10 mole % and <20 mole %;    -   TiO₂>2 mole % and <20 mole %;    -   B₂O₃≧1 mole % and ≦20 mole %; and        wherein TiO₂+Fe₂O₃ is in a range from 15 mole % to 30 mole %.

In some examples, the antimony-free glass may comprise:

-   -   V₂O₅≧40 mole % and ≦50 mole %;    -   P₂O₅≧20 mole % and <25 mole %;    -   ZnO≧2 mole % and <5 mole %;    -   Fe₂O₃>0 mole % and <20 mole %;    -   TiO₂>0 mole % and <20 mole %;    -   B₂O₃≧3 mole % and ≦20 mole %; and        wherein TiO₂+Fe₂O₃ is in a range from 15 mole % to 30 mole %.

In other examples, the antimony-free glass can comprise:

-   -   V₂O₅≧40 mole % and ≦50 mole %;    -   P₂O₅≧20 mole % and <25 mole %;    -   ZnO≧2 mole % and <5 mole %;    -   Fe₂O₃>0 mole % and <25 mole %;    -   TiO₂>0 mole % and <25 mole %;    -   B₂O₃>5 mole % and ≦20 mole %; and        wherein TiO₂+Fe₂O₃ is in a range from 15 mole % to 30 mole %.

The antimony-free glass may, for example, comprise the followingcomposition:

-   -   V₂O₅ 40 mole %;    -   P₂O₅ 20 mole %;    -   ZnO 5 mole %;    -   Fe₂O₃>7.5 mole % and <15 mole %;    -   TiO₂>7.5 mole % and <15 mole %;    -   B₂O₃>5 mole % and ≦20 mole %; and        wherein TiO₂+Fe₂O₃ is ≧15 and ≦30 mole %.

In other examples, the antimony-free glass may comprise the followingcomposition:

-   -   V₂O₅ 47.5 mole %;    -   P₂O₅≧20 mole % and <22.5 mole %;    -   ZnO 2.5 mole %;    -   Fe₂O₃>12.5 mole % and <17 mole %;    -   TiO₂>2.5 mole % and <9.5 mole %;    -   B₂O₃>1 mole % and ≦15 mole %; and        wherein TiO₂+Fe₂O₃ is ≧15 and ≦26.5 mole %.

The antimony-free glass can have a T_(g)≦365° C., such as a Tg≦350° C.

In some embodiments, the antimony-free glass may be a component in afrit for sealing together glass articles, such as glass plates in orderto form, for example, a glass package. The frit may further comprise aCTE lowering filler, such as β-eucryptite or β-quartz.

In some embodiments of the antimony-free glass, TiO₂+Fe₂O₃+B₂O₃ may bein a range from 25 mole % to 35 mole %.

In some embodiments of the antimony-free glass, TiO₂+Fe₂O₃+B₂O₃ may bein a range from 27.5 mole % to 35 mole %.

In another embodiment discloses herein a glass frit is disclosedcomprising:

-   -   V₂O₅≧40 mole % and ≦50 mole %;    -   P₂O₅≧20 mole % and <25 mole %;    -   ZnO≧0 mole % and ≦10 mole %;    -   Fe₂O₃>0 mole % and <25 mole %;    -   TiO₂>0 mole % and <25 mole %;    -   B₂O₃>0 mole % and ≦20 mole %; and        wherein TiO₂+Fe₂O₃ is in a range from 15 mole % to 30 mole %.

In certain examples, TiO₂+Fe₂O₃+B₂O₃ may be in a range from 25 mole % to35 mole %.

In some examples, the glass frit further comprises a CTE-lowering fillersuch as β-eucryptite or β-quartz.

In another aspect, a glass package is described comprising a first glassplate, a second glass plate and a frit that connects the first glassplate to the second glass plate and forms an hermetic seal therebetween,the frit including an antimony-free glass comprising:

-   -   V₂O₅≧40 mole % and ≦50 mole %;    -   P₂O₅≧20 mole % and <25 mole %;    -   ZnO≧0 mole % and ≦10 mole %;    -   Fe₂O₃>0 mole % and <25 mole %;    -   TiO₂>0 mole % and <25 mole %;    -   B₂O₃>0 mole % and ≦20 mole %; and        wherein TiO₂+Fe₂O₃ is in a range from 15 mole % to 30 mole %.

In some embodiments of the glass package TiO₂+Fe₂O₃+B₂O₃ may be in arange from 25 mole % to 35 mole %.

In some embodiment of the glass package TiO₂+Fe₂O₃+B₂O₃ may be in arange from 27.5 mole % to 35 mole %.

The glass package may further comprise an organic material disposedbetween the first and second glass plates. For example, the glasspackage may include an organic light emitting device such as an organiclight emitting diode.

The invention will be understood more easily and other objects,characteristics, details and advantages thereof will become more clearlyapparent in the course of the following explanatory description, whichis given, without in any way implying a limitation, with reference tothe attached Figures. It is intended that all such additional systems,methods, features and advantages be included within this description, bewithin the scope of the present invention, and be protected by theaccompanying claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross sectional illustration of the sealing of an exemplaryOLED device using a frit according to embodiments of the presentinvention;

FIG. 2 is a plot of coefficient of thermal expansion (CTE) as a functionof the substitution of Fe₂O₃ for TiO₂ in an Sb-free frit according toembodiments of the present invention in mole % where Fe₂O₃+TiO₂ isbetween 20 mole % and 35 mole %;

FIG. 3 is a plot comparing CTE as a function of temperature for anSb-free frit according to embodiments of the present invention and anSb-containing frit under both heating and cooling conditions;

FIG. 4 is a photograph of the supernatant after temperature and humidityexposure of boron-containing antimony-free glasses compared to anantimony-containing glass;

FIG. 5 is a graph of glass transition temperature of bothantimony-containing and antimony-free glasses as a function of B₂O₃concentration;

FIGS. 6 and 7 are photographs of the supernatant after temperature andhumidity exposure of various compositions of boron-containingantimony-free glasses as disclosed herein;

FIG. 8 is a top-down view of a portion of a glass package showing a sealmade with a frit comprising a boron-containing antimony-free glass asdisclosed herein.

DETAILED DESCRIPTION

In the following detailed description, for purposes of explanation andnot limitation, example embodiments disclosing specific details are setforth to provide a thorough understanding of the present invention.However, it will be apparent to one having ordinary skill in the art,having had the benefit of the present disclosure, that the presentinvention may be practiced in other embodiments that depart from thespecific details disclosed herein. Moreover, descriptions of well-knowndevices, methods and materials may be omitted so as not to obscure thedescription of the present invention. Finally, wherever applicable, likereference numerals refer to like elements.

FIG. 1 depicts a cross-sectional side view illustrating the sealing ofthe basic components of a hermetically sealed OLED display 10. OLEDdisplay 10 includes a multilayer sandwich of a first glass substrateplate 12, one or more OLEDs 14, frit 16 and a second glass substrateplate 18. OLED display 10 comprises hermetic seal 18 formed from frit 16that protects OLEDs 14 located between the first glass substrate plate12 and the second glass substrate plate 18. Hermetic seal 20 istypically located around the perimeter of OLED display 10. OLEDs 14 arelocated within a perimeter of hermetic seal 20. The composition of frit16, and more particularly the composition of the glass of frit 16, aswell as how the hermetic seal 20 is formed from frit 16 is described ingreater detail below.

In one embodiment, first and second substrate plates 12 and 18 aretransparent glass plates. Frit 16 is deposited along the edges of secondglass substrate plate 18. For instance, frit 16 can be placedapproximately 1 mm away from the free edges of the second glasssubstrate plate 18. In the preferred embodiment, frit 16 is a lowtemperature antimony-free glass frit containing vanadium to enhance theoptical absorbance of the frit. Frit 16 may also include a fillermaterial, such as beta eucryptite or beta quartz, that lowers thecoefficient of thermal expansion (CTE) of the frit so that it matches orsubstantially matches the CTEs of the two glass substrate plates 12 and18.

OLEDs 14 and other circuitry are deposited onto second glass substrateplate 18. The typical OLED 14 includes an anode electrode, one or moreorganic layers and a cathode electrode. However, it should be readilyappreciated that other environmentally sensitive components can bedeposited onto second glass substrate plate 18.

Optionally, frit 16 can be pre-sintered to first glass substrate plate12 prior to sealing glass substrates 12 and 18 together. To accomplishthis, first substrate plate 12 comprising frit 16 deposited thereon isheated in a furnace or oven so that it becomes attached to the firstglass substrate plate 12.

Next, first and second glass substrate plates 12 and 18 are broughttogether with frit 16 with one or more OLEDs positioned between them,and frit 16 is irradiated by irradiation source 22 (e.g. a laser or aninfrared lamp) so that the frit 16 forms hermetic seal 20 that connectsand bonds first substrate plate 12 to second substrate plate 18.Hermetic seal 18 also protects OLEDs 14 by preventing oxygen andmoisture in the ambient environment from entering into the OLED display10.

It should be readily appreciated that the irradiating wavelength shouldbe within the band of high absorption in the particular frit 16. Forinstance, Ytterbium (900 nm<λ<1200 nm), Nd:YAG (λ=1064 nm), Nd:YALO(λ=1.08 μm), and erbium (λ≈1.5 μm) CW lasers can be used depending onthe optical properties of the particular frit 16 and glass substrateplates 12 and 18.

It should also be noted that most traditional low temperature sealingfrits are PbO-based, because PbO frits have good flow, and adhesionproperties. However, the antimony-free frits disclosed herein not onlyhave a lower CTE than PbO-based frits, but also possess better aqueousdurability, as well as being comparable to the traditional Pb-basedfrits with respect to adhesion.

In addition, although the role played by P₂O₅ in a successful sealingfrit is important, since it permits stable glasses to be formed, from alaser-sealing and post-seal performance standpoint the effect of Sb₂O₃and V₂O₅ should not be ignored. In previous testing, seals made withSb-free, Zn-based vanadium-phosphate frits could only survive therelatively benign environment of 60° C./40% relative humidity (RH),while seals made from mixed Sb—Zn vanadium phosphate frits survived 60°C./85% RH before failing. Conversely, only seals made withSb-vanadium-phosphate frits survived 85° C./85% RH exposure. However,despite the role that Sb₂O₃ plays in improving aqueous durability,feedback from potential customers consistently raise concerns about itspresence. Moreover, Sb₂O₃ is thought to impede achieving desirably lowglass transition temperatures (Tg). Thus, recent emphasis has beenplaced on development of a glass suitable for a sealing frit that ismore environmentally friendly, noting that antimony is a toxic element.

Work on Sb₂O₃-free compositions began by first expressing a basic OLEDdevice sealing frit composition as a three component system (20 mole %Sb₂O₃-50 mole % V₂O₅-30 mole % P₂O₅), simplifying the composition to atwo component Sb₂O₃-free system (either 50 mole % V₂O₅-30 P₂O₅, 45 mole% V₂O₅-30 mole % P₂O₅, or 40 mole % V₂O₅-20 mole % P₂O₅), and thenidentifying the remaining components from the standpoint of their effecton aqueous durability, flow, glass transition temperature (T_(g)), andlaser-sealability. Both aqueous durability, laser-sealability, and flowof any candidate frit compositions needed to be comparable to theSb₂O₃-containing control sample, while the Tg requirements were relaxedwith the criterion that T_(g) had to be equal to or less than 400° C.(Frits with T_(g)>400° C. are unlikely to flow sufficiently during thepresintering step for OLED frits to be handleable in subsequentprocessing.) The following oxides were investigated as potentialsubstitutes for antimony (Sb₂O₃): WO₃, MoO₃, TeO₂, Bi₂O₃, Fe₂O₃, andTiO₂. ZnO was also investigated, although in view of the poor durabilityresults obtained for a ZnO—V₂O₅—P₂O₅ frit, it was considered only as aminor component (5-10 mole %) to lower T_(g) and maintain flow. Thevarious oxides selected were chosen on the basis that they formed stablebinary glasses with V₂O₅.

All of the compositions investigated were melted, poured as glasspatties, then ball-milled to form fine-particle frits (typically with ad₅₀=3-5 μm). A key bench test to screen the different compositions wasto prepare and fire flow buttons of the various frits, and then toassess their aqueous durability. The flow buttons were fired in N₂ to400° C.-450° C. (depending upon T_(g) and crystallization tendency).After firing, the flow buttons were immersed in 90° C. deionized waterfor 48 hours to assess their aqueous durability. Control samples of theOLED frit (either as the D1 base glass, or as a 70:30 by weight blend ofthe base glass with a β-eucryptite filler material) were also includedin each evaluation. Of the potential replacements for Sb₂O₃ that wereinvestigated (see above), only TiO₂ and Fe₂O₃ appeared promising.

Listed in Tables 1 and 2 are results for a 50 mole % V₂O₅ —30 mole %P₂O₅ composition series with WO₃, MoO₃, WO₃+ZnO, Bi₂O₃, and TeO₂ as thethird component. Also shown are data on the standard OLED base glass,D1, as a comparison standard. All compositions (given in mole %) wereevaluated for quality of glass formed from the pour, glass transitiontemperature (T_(g)) by DSC, flow and sinterability as a 3 μm powderhand-pressed into a pellet (“flow button”) and fired at 400° C. for 1hour in N₂, and aqueous durability (as gauged by the color of thesupernatant for a fired flow button sample—the darker the color, theless durable the sample) in the bench aqueous durability test describedabove. Note that none of the potential Sb₂O₃ replacements listed inTables 1 and 2 produced the acceptable level of glass quality, T_(g),flow, and aqueous durability exhibited by the Sb₂O₃-containing control(as judged by the appearance of the supernatant after 48 hrs, 90° C.deionized H₂O).

TABLE 1 D1 (control) D2 D3 Composition Sb₂O₃, 22.9 V₂O₅, 50 V₂O₅, 50(molar basis) V₂O₅, 46.4 P₂O₅, 30 P₂O₅, 30 P₂O₅, 26.3 WO₃, 20 MoO₃, 20Fe₂O₃, 2.4 Al₂O₃, 1.0 TiO₂, 1.0 Glass quality Excellent Fluid, good Veryfluid, at pour quality good quality T_(g) 355° C. 349° C. 315° C. Flow(400°- Very good Semi-glossy, Glossy and 1 hr, N₂) flow andwell-sintered, black with sinterability no flow some slump Aqueous V.slightly tinted Black Black durability, appearance of supernatant (48hrs, 90° C. D.I. H₂O)

TABLE 2 D4 D5 D6 Composition V₂O₅, 50 V₂O₅, 50 V₂O₅, 50 (molar basis)P₂O₅, 30 P₂O₅, 30 P₂O₅, 30 WO₃, 10 Bi₂O₃, 20 TeO₂, 20 ZnO, 10 Glassquality Good glass, fluid, Crystallized More viscous pour, at pourpoured well after pouring glass looked good T_(g) 323° C. Not eval. 329°C. Flow (400° C.- Poor flow Not eval. Semi-glossy 1 hr, N₂) black, noslump Aqueous Black Not eval. Black durability

More positive results for Sb₂O₃-free vanadium phosphate frits wereobtained by Fe₂O₃ and/or TiO₂ replacement of Sb₂O₃ (see Tables 3 and 4).All compositions are expressed in mole %. Several combinations ofFe₂O₃+TiO₂ produced good glasses at pouring. High TiO₂ glasses (i.e., 25mole %) such as D8 had acceptable T_(g) and flow properties, but alsoexhibited poor aqueous durabilities. Higher Fe₂O₃ glasses (i.e., 25 or30 mole %) such as D7 and D11 tended to produce poor glasses at pour, asevidenced by substantial surface devitrification. The relatively poorstability of these glasses (as indicated by the high amount of surfacedevitrification formed in the patty at pouring) resulted in poor flow asfrits. They also tended to be unstable with respect to oxidation state,with a fired flow button from the same lot of powder alternatelyappearing either black (reduced) or red (oxidized) after the same firingconditions. Also included in Table 4 is D14, a glass with relativelyhigh Fe₂O₃ and TiO₂ levels, but with 10 mole % ZnO to lower the expectedincrease in T_(g) from the Fe₂O₃. Note that a second approach toaccommodating high Fe₂O₃ levels is increasing the V₂O₅ content. But asmay be seen for D9 and D10, aqueous durability was compromised at higherV₂O₅ content.

TABLE 3 D7 D8 D9 D10 Composition V₂O₅, 45 V₂O₅, 45 V₂O₅, 50 V₂O₅, 50(molar basis) P₂O₅, 30 P₂O₅, 30 P₂O₅, 30 P₂O₅, 30 Fe₂O₃, 25 TiO₂, 25TiO₂, 15 TiO₂, 10 Fe₂O₃, 5 Fe₂O₃, 10 Glass quality Substantial PouredPoured Poured at pour surface devit nicely nicely nicely T_(g) 353° 345°323° 322° Flow (400° C., Poorly Semi-glossy Sintered, Sintered, 1 hr,N₂) sintered black, some flow slight flow no slump Aqueous Not BlackMed. Med. durability, tested green green appearance of supernatant (48hrs, 90° C. D.I. H₂O)

TABLE 4 D11 D12 D13 D14 Composition V₂O₅, 42 V₂O₅, 40 V₂O₅, 45 V₂O₅, 40(molar basis) P₂O₅, 28 P₂O₅, 25 P₂O₅, 25 P₂O₅, 20 TiO₂, 0 TiO₂, 17.5TiO₂, 0 TiO₂, 15 Fe₂O₃, 30 Fe₂O₃, 17.5 Fe₂O₃, 30 Fe₂O₃, 15 ZnO, 10 Glassquality Viscous, Good glass, Viscous, Good glass, at pour surface nodevit surface no devit devit devit T_(g) 371° 364° 376° 360° Flow (400°C., Poor - powdery Poor - Poor Semi-glossy 1 hr, N₂) and uncon- powderyblack, solidated sintered, no slump Aqueous Not eval. Not eval. Noteval. Lt. brown durability

It should also be noted that although the test samples of Tables 3 and 4having P₂O₅ levels equal to or greater than 25 mole % performed poorly,it is anticipated that P₂O₅ levels less than 25 mole % can besuccessfully employed. Table 5 summarizes the results of a second set ofFe₂O₃ and TiO₂ melts at 10 mole % ZnO. All compositions are expressed inmole %. As for the initial series, some combination of Fe₂O₃ and TiO₂ ispreferred, since Fe₂O₃ contributes excellent aqueous durability (but atthe cost of high T_(g) and reduced frit sintering at 400°), and TiO₂results in lower T_(g) and improved flow (but at the cost of aqueousdurability).

TABLE 5 D15 D16 D17 D18 D19 Composition V₂O₅, 50 V₂O₅, 50 V₂O₅, 50 V₂O₅,50 V₂O₅, 50 (molar basis) P₂O₅, 20 P₂O₅, 20 P₂O₅, 20 P₂O₅, 20 P₂O₅, 20ZnO, 10 ZnO, 10 ZnO, 10 ZnO, 10 ZnO, 10 Fe₂O₃, 0 Fe₂O₃, 5 Fe₂O₃, 10Fe₂O₃, 15 Fe₂O₃, 20 TiO₂, 20 TiO₂, 15 TiO₂, 10 TiO₂, 5 TiO₂, 0 Glassquality Poured Poured Poured Poured Poured at pour nicely nicely nicelynicely nicely T_(g) 297° 310° 322° 333° 348° Flow (400°- Well- Well-Sintered, Sintered, Sintered, 1 hr, N₂) sintered, sintered, slight flowsome flow little flow good flow good flow Aqueous Dark Dark Dark blackClear Clear durability black black

An additional series of melts were made at higher levels of [Fe₂O₃+TiO₂]with ZnO maintained at 5 mole % (see Tables 6 and 7 below). Allcompositions are expressed in mole %. Note that to accommodate thehigher T_(g) of the high Fe₂O₃ glasses, flow was evaluated at 425° C.,rather than the 400° C. previously used.

TABLE 6 D20 D21 D22 D23 Composition V₂O₅, 40 V₂O₅, 40 V₂O₅, 40 V₂O₅, 40(molar basis) P₂O₅, 20 P₂O₅, 20 P₂O₅, 20 P₂O₅, 20 ZnO, 5 ZnO, 5 ZnO, 5ZnO, 5 Fe₂O₃, 35 Fe₂O₃, 30 Fe₂O₃, 25 Fe₂O₃, 20 TiO₂, 0 TiO₂, 5 TiO₂, 10TiO₂, 15 Glass quality Substantial Surface Surface Good glass, at poursurface + devit devit no devit bulk devit T_(g) 416° 407° 400° 389° Flow(425°- Not Not Not Sintered, 1 hr, N₂) sinterable sinterable sinterableno flow at 425° at 425° at 425° Aq. durability Not tested Not tested Nottested Clear

TABLE 7 D24 D25 D26 D27 D28 Composition V₂O₅, 40 V₂O₅, 40 V₂O₅, 40 V₂O₅,40 V₂O₅, 40 (molar basis) P₂O₅, 20 P₂O₅, 20 P₂O₅, 20 P₂O₅, 20 P₂O₅, 20ZnO, 5 ZnO, 5 ZnO, 5 ZnO, 5 ZnO, 5 Fe₂O₃, 17.5 Fe₂O₃, 15 Fe₂O₃, 10Fe₂O₃, 5 Fe₂O₃, 0 TiO₂, 17.5 TiO₂, 20 TiO₂, 25 TiO₂, 30 TiO₂, 35 Glassquality Good glass, Good glass, Good glass, Good glass, Good glass, atpour no devit no devit no devit no devit no devit T_(g) 379° 367° 351°333° 324° Flow (425°- Sintered, Sintered Sintered, Sintered, Sintered, 1hr, N₂) slight flow slight flow mod. flow mod. flow good flow Aq. Clearwith v. Clear Med. green Med. green Med. green durability slight tint(residue) (residue)

As seen in previous results from Tables 1, 2 and 3, 4, Fe₂O₃ levels notmuch higher than 20 mole % (e.g. about 25 mole %) resulted in frits withhigh T_(g), poor stability, and unacceptable flow during 400° C.-425° C.sintering. Similarly, TiO₂ not much higher than 20 mole % (e.g. about 25mole %), resulted in frits with acceptable T_(g), flow, and stability,but with unacceptable aqueous durability. Frits with Fe₂O₃ levelsranging between from about 10 mole % to less than 25 mole %, and withTiO₂ levels from about 15 mole % to less than 25 mole % (at 5-10 mole %ZnO) combine excellent aqueous durability with acceptable flow, T_(g),and glass stability.

The aqueous durability of the (Fe₂O₃+TiO₂+ZnO) Sb₂O₃-free V₂O₅—P₂O₅frits were found to be comparable to or slightly superior to theSb₂O₃-containing standard composition. An unexpected result of theSb₂O₃-free work is that the coefficient of thermal expansion (CTE)becomes dramatically lower for the (Fe₂O₃+TiO₂+ZnO) frits at higherFe₂O₃ levels. Shown below in FIG. 2 are CTE data for sintered fritswhose composition is listed in Tables 3, 4 and 5. Data are presented forall sinterable frits in the 20 mole % (Fe₂O₃+TiO₂) series of Tables 3,4, (curve 120) and for the 35 mole % (Fe₂O₃+TiO₂) series of Table 5 asindicated by curve 122. CTE data for sintered frit bars are plotted as afunction of Fe₂O₃ level in each series up to 20 mole % Fe₂O₃, theapparent upper limit to achieving frits with good sinterability andoxidative stability. Note that CTE values are highest at 0 mole %Fe₂O₃/maximum TiO₂ (20 mole % and 35 mole %, respectively), becomeessentially constant with increasing Fe₂O₃ level at 60-65×10⁻⁷/° C., andthen decrease substantially at Fe₂O₃>15 mole % (5 mole % and 20 mole %TiO₂, respectively), reaching a value of approximately 40×10⁻⁷/° C. at17.5-20 mole % Fe₂O₃. By comparison, the CTE of the Sb₂O₃-containingbase frit is approximately 70-80×10⁻⁷/° C.

A more direct comparison of CTE between the Sb₂O₃-containing andSb₂O₃-free frits is shown in FIG. 3 where CTE curves are plotted for D1under both heating and cooling conditions (curves 124 and 126,respectively) and D29 (remelt of D24, Table 7) also under both heatingand cooling conditions (curves 128 and 130, respectively). With a CTEvalue of approximately 40×10⁻⁷/° C. for an unfilled frit, it ispossible, with the addition of fillers such as β-eucryptite or betaquartz, to lower the CTE value of this frit close to that of fusedsilica.

The lab scale aqueous durability results for Sb-free frits werecorroborated in a large scale sealing trial involving 85° C./85% RHexposure of laser-sealed samples. Shown in Table 8 are results of thetrial and comparison between the standard OLED frit (D1, Table 1; usedas a 70:30 blend by weight with low CTE filler β-eucryptite), and anSb-free frit (D29, remelt of D24, Table 7; used as an 80:20 wt. blendwith low CTE filler β-quartz). Each frit blend was made into a paste,dispensed on several sheets of EAGLE display glass, presintered(Sb-containing standard, heated at 325° C. for 2 hours in air+400° C.for 1 hr in N₂; Sb-free, heated at 325° C. for 2 hours in air+425° C.for 1 hour in N₂), sealed to sheets of EAGLE^(XG), placed in an 85°C./85% relative humidity (RH) environmental chamber, and then examinedperiodically for evidence of seal leakage and Ca metal breakdown. Intotal, there were 3 sheets of the Sb-containing control composition and7 sheets of the antimony-free composition included in the study, with 9sealed arrays of Ca metal tabs per sheet. As may be seen in Table 8,several arrays failed either immediately after sealing or within 100 hrsof placing them in a 85° C./85% RH chamber for both the Sb-control andthe Sb-free frits; these failures were related, most likely, to grossdefects such as contamination present at random for each frit. However,after 96 hrs, no additional failures were observed for either theSb-control or the Sb-free frit seals.

TABLE 8 No. of good cells Laser- At start After 96 After 1056 sealed of85/85 hrs of 85/85 hrs of 85/85 Standard Sb-frit blend 27 (3 25 24 24(70:30, D1:β-eucryptite) sheets) Sb-free frit blend 63 (7 61 57 57(80:20, D29:β-quartz) sheets)

In summary, the excellent aqueous durability performance of Sb-vanadiumphosphate frits was maintained without Sb₂O₃ by replacing the antimonyoxide with a combination of Fe₂O₃+TiO₂, along with a small addition ofZnO to maintain flow and glass transition temperature (T_(g)). Thepresence of Fe₂O₃ was found to have the greatest effect in improvingdurability. However, in large amounts it raised T_(g), thus degradingfrit flow during sealing. In addition, frits with high Fe₂O₃ levels(equal to or greater than about 25 mole %) tended to be oxidativelyunstable, with repeat samples fired to the same schedule (425° C. in N₂)exhibiting different colors (brown or black), with marked differences inthe degree of flow. Although TiO₂ actually degraded aqueous durabilityto some extent when added by itself, the combination of (Fe₂O₃+TiO₂)appeared to be an ideal combination from the standpoint of obtaininglaser-sealable frits with both high aqueous durability and low T_(g)(≦400° C.).

Both lab bench tests in 90° C. deionized water as well as 85° C./85% RHenvironmental chamber testing of laser-sealed samples indicate thatfrits based on the Fe₂O₃—TiO₂—ZnO—V₂O₅—P₂O₅ system are capable offorming a hermetic seal after laser-sealing that will withstand highhumidity conditions for extended times (≧1000 hrs). An unexpected resultof the (Fe₂O₃+TiO₂) replacement of Sb₂O₃ was that the CTE of the Sb-freefrit without fillers decreased by approximately half (from 70-80×10⁻⁷/°C. to 35-45×10⁻⁷/° C.), with only a minor increase in T_(g) (from 355°C. to 370° C.). Frits with CTE values near 40×10⁻⁷/° C. have thepotential, with the addition of fillers such as β-eucryptite orβ-quartz, of being able to seal fused silica and other low CTEsubstrates such as Kovar™.

However, in spite of the success in developing the foregoingantimony-free frits, the high T_(g) (380° C.) resulted in a higherpre-sintering temperature (˜425° C.) than comparable antimony-containingfrits like D1, and needed to be sustained for a longer period of time atthe pre-sintering temperature. Thus, while environmentally friendly,such antimony-free frits tend to increase process times and thereforeprocess costs. Moreover, the antimony-free frits described above werefound to crystallize to at least some extent during the pre-sinteringcycle, leading to somewhat reduced adhesion properties. Accordingly,additional work was conducted on a lower T_(g), but still Sb-free,variant. The T_(g) of this newer frit, D30, was approximately 30° C.lower than D24, and was essentially identical to D1 in T_(g) and flow.This decreased T_(g) in D30 was achieved by incorporating about 7.5 mole% more V₂O₅ at the expense of ZnO and TiO₂, indicating the role thatsmall composition changes have on certain properties of the V₂O₅—P₂O₅glasses. Shown in Table 9 is a comparison between D24 and the revisedcomposition D30. All compositional values are in mole %.

TABLE 9 D24 D30 V₂O₅ 40 47.5 P₂O₅ 20 22.5 ZnO 5 2.5 TiO₂ 17.5 10 Fe₂O₃17.5 17.5 Al₂O₃ 0 0 T_(g) 378° C. 351° C.

A key component in both D24 and D30 is Fe₂O₃, which may serve as a redoxmoderator of V₂O₅ (as did Sb₂O₃ in D1). Fe₂O₃, however, also acts toincrease T_(g). The other components of D24, namely ZnO and TiO₂, serveto counteract to some extent the role of Fe₂O₃ in raising T_(g),although they can also tend to lessen resistance to aqueous attack.

FIG. 4 shows photographs of sintered glass pellets of selected glasscompositions suitable for the manufacture of glass frits in laboratorybeakers for after being immersed in 90° C. deionized water for 48 hours.Prior to immersion the pellets were heat treated by exposing each flowbutton to 300° C. for one hour in air followed by 400° C. for one hourin nitrogen. FIG. 4 depicts, in order, from left to right, (a) D1, (b)D24, and (c) D30.

Although the lowering of T_(g) in Sb-free composition D30 to 350° C. washighly desirable, further composition efforts were undertaken todetermine whether additional decreases in T_(g) were possible.Accordingly, B₂O₃, a low T_(g) glass former, was added. In making theB₂O₃ additions, the addition should be done in such as manner as to notdegrade glass stability, aqueous durability, and flow. Indeed, thefollowing guidelines were followed: (a) B₂O₃ should not be substitutedfor P₂O₅, since, as noted, P₂O₅ plays an important role in stabilizingthe frit. When P₂O₅ is present at moderate levels (approximately 20 mole%), the vanadate glass frit tends to exhibit minimal crystallization,and as a result, the frit exhibits an extended region of viscous flowduring the sealing process, leading to improved adhesion; (b) B₂O₃should not be substituted for V₂O₅, since, as noted, this component isimportant for good flow and low CTE; (c) Fe₂O₃ should be maintained asclose as possible to the level (17.5 mole %) present in the starting D24and D30 compositions, or durability could be impaired. However, smalldecreases in Fe₂O₃ (down to about 12.5 mole %) can be tolerated withacceptable loss in aqueous durability; and (d) to maintain glassstability, the total amount of glass former (e.g., V₂O₅+P₂O₅+B₂O₃)should be at least 60 mole %, with 65-70 mole % more preferred for glassstability. With these prescriptions in mind, B₂O₃ was added as follows:B₂O₃ for (ZnO+TiO₂+Fe₂O₃), with Fe₂O₃ maintained at ≧12.5 mole %). Itshould be noted that while the following discussion is centered aroundD1, D24 and D30, this samples are representative of families ofcompositions. For example, as shown below in Table 10, each of thesamples D31-D35 is a glass composition essentially the same as the D24composition, with the exception that B₂O₃ was substituted for Fe₂O₃ andTiO₂ in varying amounts. The same is true for Table 11, except that theglass is the D30 glass and the variations are D36-D41 (and D40 haddecreased P₂O₅).

Listed below in Table 10 is the B₂O₃ substitution series, including forreference D24. B₂O₃ was added in an amount up to 20 mole % following thesubstitution schema presented above. T_(g) decreased by approximately70° C., from a temperature of 376° C. recorded for a remelt of D24 to alow of 305° C. for D34. The onset of crystallization is designated byT_(x). All compositional values are in mole %.

TABLE 10 D24 D31 D32 D33 D34 D35 V₂O₅ 40 40 40 40 40 40 P₂O₅ 20 20 20 2020 20 B₂O₃ 0 5 7.5 10 15 20 Fe₂O₃ 17.5 15 13.7 12.5 10 7.5 TiO₂ 17.5 1513.8 12.5 10 7.5 ZnO 5 5 5 5 5 5 T_(g) 376° C. 364° C. 356° C. 348° C.325° C. 305° C. T_(x) (onset) 497° C. 507° C. 506° C. 506° C. 511° C.485° C.

Additionally, B₂O₃ substitutions were also made to D30, using thesubstitution schema presented earlier. B₂O₃ was added in an amount up to15 mole %. The glass transition temperature T_(g) for this seriesdecreased by approximately 50° C., from 351° C. to 299° C.

TABLE 11 D30 D36 D37 D38 D39 D40 D41 V₂O₅ 47.5 47.5 47.5 47.5 47.5 47.547.5 P₂O₅ 22.5 22.5 22.5 22.5 22.5 22.5 20 B₂O₃ 0 1 3 5 7.5 10 15 Fe₂O₃17.5 17 16 15 13.5 12.5 12.5 TiO₂ 10 9.5 8.5 7.5 6.5 5 2.5 ZnO 2.5 2.52.5 2.5 2.5 2.5 2.5 T_(g) 351° 350° 345° 331° 320° 311° 299° T_(x)(onset) 493° 476° 442° 510° 512° 515° 511°

FIG. 5 is a graph illustrating the effect of including boron (B₂O₃) incertain frit glasses. For example, curve 200 depicts the effect on T_(g)for varying amounts of B₂O₃ in the general composition for D24, whilecurve 202 depicts the effect on T_(g) for varying amounts of B₂O₃ in thegeneral composition for D30. Note that the addition of B₂O₃ into theseglasses resulted in a monotonic, linear decrease in T_(g), indicatingthat no abrupt structural changes are occurring in the base vanadiumphosphate glass with boron addition over the composition range studied.Equally interesting is the data represented by curve 204, wherein B₂O₃was added to the glass of D1, an antimony-containing glass. Curve 204illustrates virtually no change in T_(g), suggesting that the simpleaddition of boron per se may not result in a significant effect onT_(g).

FIG. 6 shows photographs of sintered glass frit pellets in laboratorybeakers for D24 glass, with varying amounts of B₂O₃ added, after beingimmersed in 90° C. deionized water for 48 hours. The pellets wereproduced by forming a glass melt, grinding the solidified glass to forma glass frit, compressing the frit into pellets and sintering thepellets by exposing each pellet to 300° C. for one hour in air followedby 400° C. for one hour in nitrogen. FIG. 6 depicts, in order, from leftto right, (a) 0 mole % B₂O₃, (b) 5 mole % B₂O₃, (c) 7.5 mole % B₂O₃, (d)10 mole % B₂O₃, (e) 15 mole % B₂O₃, and (f) 20 mole % B₂O₃. Aqueousdurability can be judged based on the “darkness” (opacity) of thesupernatant. The darker the supernatant, the less durable the glass. Theresults shown in FIG. 6 indicate acceptable aqueous durability for B₂O₃in amounts up to about 10 mole %. It should be understood, however, thatthe acceptability of aqueous durability will depend on the end use ofthe glass.

FIG. 7 shows photographs of sintered glass pellets in laboratory beakersfor D30 glass, with varying amounts of B₂O₃ added, after being immersedin 90° C. deionized water for 48 hours. The pellets were produced asabove, by forming a glass melt, grinding the solidified glass to form aglass frit, compressing the frit into pellets and sintering the pelletsby exposing each pellet to 300° C. for one hour in air followed by 400°C. for one hour in nitrogen. FIG. 7 depicts, in order, from left toright, (a) 0 mole % B₂O₃, (b) 1 mole % B₂O₃, (c) 3 mole % B₂O₃, (d) 5mole % B₂O₃, (e) 7.5 mole % B₂O₃, (f) 10 mole % B₂O₃, and 15 mole %B₂O₃. As illustrated, aqueous durability in the samples of FIG. 7 areimproved over a range from about 5 mole % to about 7.5 mole %, comparedwith other concentrations shown.

Shown in FIG. 8 is a bright field image of a section of a laser-sealedsection of two LOTUS^(XT) display glasses 12, 18 sealed with a frit 16made with a blend of the 5 mole % B₂O₃-modified D30 frit and aCTE-lowering glass-ceramic filler using a method as previously describedin the present disclosure. The view in looking downward through glasssubstrate 12 to glass substrate 18. The frit connecting the glass platesincludes a sealed portion 206 and unsealed portions 208. Note that thewidth 210 of the sealed portion of the frit, i.e. that portion of thefrit actually bonded to the glass substrates, is approximately 90% ofthe total frit width 212 (968 μm/1083 μm=89.38%), indicating excellentflow and sealing behavior for a boron-containing, antimony-free frit asdisclosed herein.

Sb-free frits containing boron (B₂O₃) are described for sealingelectronic devices, such as OLED displays, that offercomparable-to-lower Tg and comparable-to-improved aqueous durabilitythan current Sb-containing frits, such as represented by D1. These sameboron-containing Sb-free frits also possess lower Tg and comparableaqueous durability than non-boron-containing but Sb-free frits.

Although embodiments disclosed herein have been illustrated in theaccompanying Drawings and described in the foregoing DetailedDescription, it should be understood that these embodiments are notlimited to those disclosed, but are capable of numerous rearrangements,modifications and substitutions without departing from the spirit of thedisclosure as set forth and defined by the following claims.

What is claimed is:
 1. An antimony-free glass comprising: V₂O₅≧40 mole %and ≦52.5 mole %; P₂O₅≧15 mole % and <25 mole %; ZnO≧0 mole % and ≦10mole %; Fe₂O₃>0 mole % and <25 mole %; TiO₂>0 mole % and <25 mole %;B₂O₃>0 mole % and ≦20 mole %; and wherein TiO₂+Fe₂O₃ is in a range from15 mole % to 30 mole %, and wherein the antimony-free glass has aT_(g)≦365° C.
 2. The antimony-free glass according to claim 1,comprising: V₂O₅≧40 mole % and ≦52.5 mole %; P₂O₅≧20 mole % and <25 mole%; ZnO≧0 mole % and ≦5 mole %; Fe₂O₃≧10 mole % and <20 mole %; TiO₂>2mole % and <20 mole %; B₂O₃≧1 mole % and ≦20 mole %; and whereinTiO₂+Fe₂O₃ is in a range from 15 mole % to 30 mole %.
 3. Theantimony-free glass according to claim 1, comprising: V₂O₅≧40 mole % and≦50 mole %; P₂O₅≧20 mole % and <25 mole %; ZnO≧2 mole % and <5 mole %;Fe₂O₃>0 mole % and <20 mole %; TiO₂>0 mole % and <20 mole %; B₂O₃≧3 mole% and ≦20 mole %; and wherein TiO₂+Fe₂O₃ is in a range from 15 mole % to30 mole %.
 4. The antimony-free glass according to claim 1, comprising:V₂O₅≧40 mole % and ≦50 mole %; P₂O₅≧20 mole % and <25 mole %; ZnO≧2 mole% and <5 mole %; Fe₂O₃>0 mole % and <25 mole %; TiO₂>0 mole % and <25mole %; B₂O₃>5 mole % and ≦20 mole %; and wherein TiO₂+Fe₂O₃ is in arange from 15 mole % to 30 mole %.
 5. The antimony-free glass accordingto claim 1, wherein the antimony-free glass has the followingcomposition: V₂O₅ 40 mole %; P₂O₅ 20 mole %; ZnO 5 mole %; Fe₂O₃>7.5mole % and <15 mole %; TiO₂>7.5 mole % and <15 mole %; B₂O₃>5 mole % and≦20 mole %; and wherein TiO₂+Fe₂O₃ is ≧15 and ≦30 mole %.
 6. Theantimony-free glass according to claim 1, wherein the antimony-freeglass has the following composition: V₂O₅ 47.5 mole %; P₂O₅≧20 mole %and <22.5 mole %; ZnO 2.5 mole %; Fe₂O₃>12.5 mole % and <17 mole %;TiO₂>2.5 mole % and <9.5 mole %; B₂O₃>1 mole % and ≦15 mole %; andwherein TiO₂+Fe₂O₃ is ≦15 and ≦26.5 mole %.
 7. The antimony-free glassaccording to claim 1, wherein the antimony-free glass has a Tg≦350° C.8. The antimony-free glass according to claim 1, wherein theantimony-free glass comprises a frit.
 9. The antimony-free glassaccording to claim 8, wherein the frit further comprises a CTE loweringfiller.
 10. The antimony-free glass according to claim 1, whereinTiO₂+Fe₂O₃+B₂O₃ is in a range from 25 mole % to 35 mole %.
 11. Theantimony-free glass according to claim 10, wherein TiO₂+Fe₂O₃+B₂O₃ is ina range from 27.5 mole % to 35 mole %.
 12. An antimony free glass fritcomprising: V₂O₅≧40 mole % and ≦52.5 mole %; P₂O₅≧20 mole % and <25 mole%; ZnO≧0 mole % and ≦10 mole %; Fe₂O₃>0 mole % and <25 mole %; TiO₂>0mole % and <25 mole %; B₂O₃>0 mole % and ≦20 mole %; and whereinTiO₂+Fe₂O₃ is in a range from 15 mole % to 30 mole %, and wherein theglass frit has a T≦365° C.
 13. The glass frit according to claim 12,wherein TiO₂+Fe₂O₃+B₂O₃ is in a range from 25 mole % to 35 mole %. 14.The glass frit according to claim 12, further comprising a CTE-loweringfiller.
 15. The glass frit according to claim 14, wherein the CTElowering filler is β-eucryptite or β-quartz.
 16. A glass packagecomprising: a first glass plate; a second glass plate; and a frit thatconnects the first glass plate to the second glass plate and forms anhermetic seal therebetween, the frit including an antimony-free glasscomprising: V₂O₅≧40 mole % and ≦52.5 mole %; P₂O₅≧20 mole % and <25 mole%; ZnO≧0 mole % and ≦10 mole %; Fe₂O₃>0 mole % and <25 mole %; TiO₂>0mole % and <25 mole %; B₂O₃>0 mole % and ≦20 mole %; andwherein—TiO₂+Fe₂O₃ is in a range from 15 mole % to 30 mole %, andwherein the antimony-free glass has a T_(g)≦365° C.
 17. The glasspackage according to claim 16, wherein TiO₂+Fe₂O₃+B₂O₃ is in a rangefrom 25 mole % to 35 mole %.
 18. The glass package according to claim16, wherein TiO₂+Fe₂O₃+B₂O₃ is in a range from 27.5 mole % to 35 mole %.19. The glass package according to claim 16, further comprising anorganic material disposed between the first and second glass plates.